Releasable catch



J. R. METZ Dec. 26, 1967 RELEASABLE CATCH Filed March 24, 1966 Jose h RMeiz AGENT United States Patent 3,359,607 RELEASABLE CATCH Joseph R.Metz, Ridgeiield, Conn., assignor to N orco, Inc., Ridgefield, Conn, acorporation of Connecticut Filed Mar. 24, 1966, Ser. No. 537,052 11Claims. (Cl. 24-239 ABSTRACT OF THE DISCLOSURE A heavy duty catch of thesnap hook type having a slidable latch releasable by a hammer blow on alongitudinally slidable release member. The latch and release membersbeing interconnected by pin and cam means which provide a mechanicaladvantage to enable a light blow to release the catch.

This invention relates to releasable clasps or catches, and moreparticularly to devices of this type which are adapted to accommodatesubstantially heavy loads or working forces.

Objects of the invention are to provide an improved releasable catchwhich is relatively easy to release even with heavy loads, and whereinthe load force aids in the release after the initial releasing actionhas taken place; to provide a catch as above, which is especiallyresistant to vibratory forces in combatting undesirable release; toprovide a catch of the type indicated, which is sturdy andfailure-resistant while at the same time being of relatively small sizeand compactly arranged; to provide an improved hook-type catch inaccordance with the foregoing, which can be released in response to arelatively light hammer blow on a release member, and also wherein suchhammer blow may be directed longitudinally of the mounting shank of thecatch body, and at either of opposite sides of the hook formation of thecatch; a catch as above, wherein an advantageous mechanical advantage iseffected in the release mechanism, enabling release of heavy loads to beaccomplished with appreciably lighter applied forces; a catch asindicated, wherein release is opposed by a spring-loaded cam lock, aswell as by an additional spring, giving assurance against accidentalrelease dueto shock, vibration and the like; and a catch which isrelatively simple, having few, functionally simple components in amechanically sound or valid assemblage, and which is of relatively lowcost.

Other features and advantages will hereinafter appear.

In the drawings:

FIG. 1 is a longitudinal sectional view of a heavy-duty vibration-proofcatch as provided by the invention, a portion of the jaw or hookformation being shown in elevation.

FIG. 2 is a top plan view of the catch of FIG. 1.

FIG. 3 is a fragmentary side elevational view of the catch, showingexterior details not seen in FIG. 1.

FIG. 4 is a side elevational view of a locking bar as provided in thecatch.

FIG. 5 is a top plan view of the locking bar of FIG. 4.

FIG. 6 is an end elevational view of the locking bar of FIGS. 4 and 5.

FIG. 7 is a side elevational view of a release bar as provided in thecatch of FIG. 1.

FIG. 8 is a top plan view of the release bar of FIG. '7.

FIG. 9 is an end elevational View of the release bar of FIGS. 7 and 8.

FIG. 10 is a front elevational view of an impact member of the catch ofFIG. 1. I

FIG. 11 is a side elevational view of the impact member of FIG. 10.

Considering first FIGS. 1-3, the catch comprises a body member 29provided with a hook formation 22 which'has Patented Dec. 26, 1967 atits lower portion a gap 24 adapted to receive a cooperable member in theform of a heavy clevis pin 26. The body 20, including the hook formation22, is of flat shape as seen in FIG. 2, having opposite sides 28, andfurther including a shank 32 having a large-diameter portion 34 and asmall-diameter portion 36.

In the body 20 there is provided a first guide channel 38 which opensinto the gap 24 of the hook formation and extends upwardly and to theright therefrom as viewed in FIG. 1 so as to be angularly disposed withrespect to the axis AA of the shank. The axis of the first guide channel38 makes an angle, indicated at X in FIG. 1, which is roughly on theorder of 35 with respect to the axis A--A of the shank.

Carried in the first guide channel 38 is a locking bar 40 shown indetail in FIGS. 4, 5 and 6. The locking bar 40 has a nose portion 42provided with a rounded bottom surface 44, a rounded tip 45 and aconcave upper surface 46 which latter is arranged to generally nest thecooperable member or pin 26 as seen in FIG. 1.

A helical compression spring 48 is disposed in the upper portion of thefirst guide channel 38 and engages the upper end of the locking bar 40and also a closure plug 50 which latter is affixed in the guide channelby a cross pin 51. Thus, the locking bar 40 is continually biased to itsadvanced, downward position as illustrated in FIG. l, where in itretains and locks in place the cooperable member 26, holding the lattersecurely in the gap 24 of the hook formation 22.

In accordance with the present invention, the improved catch isespecially resistant to release accidentally in response to shocks,vibration and the like, yet may be easily released with relativelylittle force in spite of heavy reactive forces being experienced by thelocking bar 40 due to heavy loads on the cooperable member 26. Themember 26 may be part of a structural formation (not shown) to which thehook 20 is to be releasably secured, and in turn to which any otherstructure attached to the shank 36 of the catch is to be releasablysecured.

In accomplishing a quick and easy release of the member 26 in spite ofheavy loads suffered thereby while at the same time resisting accidentalrelease of the member, there is provided by the invention a novelrelease mecha nism which is cooperable with the locking bar 40 through acam connection, said release mechanism including a second biasing orspring means, which acts on the cam connection.

Referring to FIG. 1, the body 20 of the catch is provided with a secondguide channel 52 which is shown as extending through the shank portions34 and 36 of the body. In the second guide channel 52 there is a releasebar 54 (see also FIGS. 7, 8 and 9) having a cam slot 56, a front camportion 58, and a back cam portion 60. The release bar 54 has acylindrical body portion 62, whereas the cam portions 58, 60 comprise arelatively thin front extension designated generally by the numeral 64.

To accommodate the cam extension 64 of the release bar, the locking bar40 has a longitudinal slot 66 arranged to slidably receive saidextension, In the slot 66 there is a fixed cross pin 68 which is adaptedto be received in the cam slot 56 of the release bar 54, and to be actedon by the cam portions 58, 60' of said bar.

The release bar 54 is continually urged or biased forwardly or to theleft by a helical compression spring 70 disposed in the second guidechannel 52 and engaging the back end of the release bar as well as anabutment 72 carried by the shank portion 36.

For the purpose of actuating the release bar or cam lock 54, an operatoris provided, comprising an irnpace member 74 in the form of an annuluswhich is longitudinally slidable on the shank portion 34 of the body20'. The said shank portion is provided with diametric slots 76, inwhich there is disposed a cross pin 78 passing through the release bar40 and also the annulus 74 and constituting a connecting means betweensaid bar and annulus. The impact member or annulus 74 hasimpactresistant formations or lugs 80 adapted to receive a hammer blow,by which a forcible retraction or left-to-right movement of the releasebar 54 may be effected.

The operation of the catch is as follows: Referring to FIG. 1, the partsare shown in the locking position, with the cooperable member 26forcibly retained in the hook formation 22 of the catch body 20. It willbe noted that the cam portion 60 of the release bar is in engagementwith the follower pin 68 of the locking bar 40, and is held in suchengagement under continual force as exerted by the helical compressionspring 70. The locking bar 40 is thus securely retained in its advanced,locking position, being held therein not only by such cam engagement butalso by the locking-bar spring 48, and by frictional forces.

By virtue of the two springs 48, 70 both tending to retain the lockingbar 40 in the advanced position, and by virtue of the cam engagementbetween the cam portion 60 of the release bar and the follower pin 68 ofthe locking bar there is virtually no possibility for the catch to beaccidentally released, even though considerable forces are experiencedand considerable loads are carried by the cooperable member 26 and hookformation 22.

When it is desired to release the member 26 from the hook formation, itis only necessary to strike the impact member 74, as by a hammer blow,on either of the lugs 80 thereof. This will effect a retraction of therelease bar 54 against the action of the spring 70, and the cam portion58 now comes into play, engaging the follower pin 68 and forciblyretracting the locking bar 40 against the action of the spring 48. Byvirtue of the rounded configuration of the cooperable member or pin 26,the initial retracting movement of the locking bar 40 will besupplemented by an additional retracting force due to the camming effectof said rounded surface of the pin 26 against the rounded nose portion42 of the locking bar.

The releasing movement of the cooperable member or pin 26 will bedownward, along an axis or direction indicated at BB, such axis makingan angle of roughly 90 with the axis AA of the shank 32 of the catch. Inaiding the retraction of the locking bar 40, the pin 26 will shift alonga guiding edge 84 of the hook formation, as seen in FIG. 1.

I have found that with the above construction a numberof advantages arehad, in a heavy-duty catch. For in stance, the arrangement of the guidechannels and the locking and release bars enables a relatively shallowmouth to be provided on the hook formation 22. Once the initialreleasing movement of the locking bar 40 is efiected, the load forcesexperienced by the pin 26 and the rounded shape of such pin will tend toinsure a complete release of the pin by a cam action which effects afull retraction of the locking bar. However, prior to any initialreleasing movement, the locking bar 40 will be securely held in itsadvanced position due to its spring 48 and also the cam connection withthe release bar 54 which is under the action of the advancing spring 70.Upon the impact member 74 suffering a hammer blow, the release bar 54can effect a retraction of the locking bar with relatively small force,due to the camming action provided by the cam portion 58, whichrepresents .a mechanical advantage. Such mechanical advantage resultssince the release bar 54 has much greater movement than the locking bar40. The same mechanical advantage also exists when the releasebar 54 ismaintaining the locking bar 40' in the advanced position, due to the camportion 60 as will be understood. v

Thecatch as above described is sturdy and failure-resistant, while atthe same time being of relatively small size and compactly arranged. Thedirection of the ham mer blow islongitudinally of the mounting shank 32of the catch body and may be applied at either of opposite sides of thehook formation of the body. The catch is relatively simple and has few,functionally simple components in a mechanically sound or validassemblage, and is of relatively low cost. Accidental release of thecatch is positively prevented by the multiple springs and the cam lockconnection comprising the release bar 54 acting on the locking bar 40.

Variations and modifications may be made within the scope of the claims,and portions of the improvement may be used without others.

I claim:

1. A heavy duty releasable catch comprising, in combination:

(a) a body having a hook formation including a downwardly open gap, afirst guide channel which opens into a gap of the hook, and a secondguide channel communicating with said first guide channel,

(b) a locking bar movable longitudinally in said first guide channelbetween an advanced position enabling one end thereof to protrude intosaid hook gap to lock a cooperable member received therein and aretracted position wherein the end is withdrawn from the gap for freeingsaid member,

(c) yieldable means urging said locking bar to advanced position,

(d) a release bar slidable in said second guide channel between extendedand retracted positions,

(e) an operable member slidably carried by said hook body on theexterior thereof, said operable member having means engageable with aforce-applying instrumentality to effect its movement,

(f) means connecting said operable member and said locking bar forsimultaneous movement,

(g) cooperable means connected with said bars, effecting a retraction ofthe locking bar in response to retracting movement of the release bar ina direction away from said first guide channel, and

(11) means biasing said release bar to extended position.

2. A heavy duty releasable catch as in claim 1, wherein:

a) the gap of the hook formation has an inner guiding edge at one side,which engages, and determines the direction of removal of, thecooperable member,

(b) said first guide channel extending angularly upward from the gap ofthe hook and having an axis making an angle between and 180 with theguided direction of removal of the said cooperable member.

3. A heavy duty releasable catch as in claim 2,

wherein:

(a) the angle between the axis of the first channel and the direction ofremoval of the cooperable member is roughly 4. A heavy duty releasablecatch as in claim 2, wherein:

(a) the axis of the said second guide channel is substantially at rightangles to the direction of removal of the said cooperable member.

5. A heavy duty releasable catch as in claim 2, wherein:

(a) the locking bar has a nose portion provided with a rounded edge forengagement with a rounded surface of said cooperable member.

' 6. A heavy duty releasable catch as in claim 5, where- 1n:

(:1) the nose portion of the locking bar is of tapered cross section,

(b) said nose portion having an upper concave surface adapted generallyto nest the cooperable member and having a rounded bottom surfaceengageable by the cooperable member when entering said gap, tomomentarily cam the locking bar to retracted position.

7. A heavy duty releasable catch as in claim 1, where- (a) the saidoperable member has impact-resistant portions adapted to be struck by ahammer.

s. A heavy duty releasable catch as in claim 7, where- (a) the operablemember comprises an annulus slidable on the said shank,

(b) said impact-resistant portions comprising a pair of lugs disposed onopposite sides of, and projecting from, said annulus.

9. A heavy duty releasable catch as in claim 1, where- (a) cooperablemeans are provided on said bars, maintaining the locking bar inextended, locking position when the release bar is maintained extended.

10. A heavy duty releasable catch as in claim 9, where (a) the two saidcooperable means on the locking and release bars comprise cam and camfollower devices respectively on said bars, providing a mechanical ad- 6vantage wherein the release bar has a greater movement than the lockingbar.

11. A heavy duty releasable catch as in claim 1, where- (a) thecooperable means on the locking and release bars comprise a cam and camfollower respectively on said bars, providing a mechanical advantagewherein the release bar has the greater movement.

References Cited UNITED STATES PATENTS 761,859 6/ 1904 Sweet. 1,051,4281/1913 MoLeran 24-239 XR 1,062,653 5/ 191-3 Koons. 1,198,139 9/1916Lyon. 1,228,513 6/ 1917 Anderson.

DONALD A. GRIFFIN, Primary Examiner.

1. A HEAVY DUTY RELEASABLE CATCH COMPRISING, IN COMBINATION: (A) A BODYHAVING A HOOK FORMATION INCLUDING A DOWNWARDLY OPEN GAP, A FIRST GUIDECHANNEL WHICH OPENS INTO A GAP OF THE HOOK, AND A SECOND GUIDE CHANNELCOMMUNICATING WITH SAID FIRST GUIDE CHANNEL, (B) A LOCKING BAR MOVABLELONGITUDINALLY IN SAID FIRST GUIDE CHANNEL BETWEEN AN ADVANCED POSITIONENABLING ONE END THEREOF TO PROTRUDE INTO SAID HOOK GAP TO LOCK ACOOPERABLE MEMBER RECEIVED THEREIN AND A RETRACTED POSITION WHEREIN THEEND IS WITHDRAWN FROM THE GAP FOR FREEING SAID MEMBER, (C) YIELDABLEMEANS URGING SAID LOCKING BAR TO ADVANCED POSITION, (D) A RELEASE BARSLIDABLE IN SAID SECOND GUIDE CHANNEL BETWEEN EXTENDED AND RETRACTEDPOSITION,